Blood basophils from cystic fibrosis patients with allergic bronchopulmonary aspergillosis are primed and hyper-responsive to stimulation by aspergillus allergens

IntroductionFifteen to sixty percent of cystic fibrosis patients harbor Aspergillus fumigatus (Af) in their airways (CF-AC) and some will develop allergic bronchopulmonary aspergillosis (CF-ABPA). Since basophils play a key role in allergy, we hypothesized that they would display alterations in CF-ABPA patients compared to CF-AC or patients without Af colonization (CF).MethodsUsing flow cytometry, we measured CD203c, CD63 and CD123 levels on basophils from CF-ABPA (N = 11), CF-AC (N = 14), and CF (N = 12) patients before and after ex vivo stimulation with Af allergens.ResultsBaseline CD203c was increased in basophils from CF-ABPA compared to CF-AC and CF patients. Af extract and recombinant Aspf1 stimulated basophils from CF-ABPA patients to markedly upregulate CD203c, along with modest upregulation of CD63 and a CD123 downward trend. Plasma TARC/CCL17 at baseline and post-stimulation cell supernatant histamine levels were similar in the three groups.ConclusionsIn CF-ABPA, blood basophils are primed and hyperresponsive to Af allergen stimulation.